Serum PD-1 Levels Change with Immunotherapy Response but Do Not Predict Prognosis in Patients with Hepatocellular Carcinoma

Blood-based biomarkers for immune-based therapy in advanced HCC: Promising but a long way to go

The introduction of immune checkpoint inhibitors (ICIs) represents a key shift in the management strategy for patients with hepatocellular carcinoma (HCC). However, there is a paucity of predictive biomarkers that facilitate the identification of patients that would respond to ICI therapy. Although several researchers have attempted to resolve the issue, the data is insufficient to alter daily clinical practice. The use of minimally invasive procedures to obtain patient-derived specimen, such as using blood-based samples, is increasingly preferred. Circulating tumor DNA (ctDNA) can be isolated from the blood of cancer patients, and liquid biopsies can provide sufficient material to enable ongoing monitoring of HCC. This is particularly significant for patients for whom surgery is not indicated, including those with advanced HCC. In this review, we summarize the current state of understanding of blood-based biomarkers for ICI-based therapy in advanced HCC, which is promising despite there is still a long way to go.

Interfacial interactions of SERS-active noble metal nanostructures with functional ligands for diagnostic analysis of protein cancer markers

Noble metal nanostructures with designed hot spots have been widely investigated as surface-enhanced Raman spectroscopy (SERS)-active substrates, particularly for selective and sensitive detection of protein cancer markers. For specific target recognition and efficient signal amplification, SERS probe design requires a choice of SERS-active nanostructures as well as their controlled functionalization with Raman dyes and target recognition entities such as antibodies. However, the chemical conjugation of antibodies and Raman dyes to SERS substrates has rarely been discussed to date, despite their substantial roles in detection schemes. The interfacial interactions of metal nanostructures with functional ligands during conjugation are known to be strongly influenced by the various chemical and physical properties of the ligands, such as size, molecular weight, surface charge, 3-dimensional structures, and hydrophilicity/hydrophobicity. In this review, we discuss recent developments in the design of SERS probes over the last 4 years, focusing on their conjugation chemistry for functionalization. A strong preference for covalent bonding is observed with Raman dyes having simpler molecular structures, whereas more complicated ones are non-covalently adsorbed. Antibodies are both covalently and non-covalently bonded to nanostructures, depending on their activity in the SERS probes. Considering that ligand conjugation is highly important for chemical stability, biocompatibility, and functionality of SERS probes, this review is expected to expand the understanding of their interfacial design, leading to SERS as one of the most promising spectroscopic analytical tools for the early detection of protein cancer markers.

Serum levels of soluble programmed death-ligand 1 (sPD-L1): A possible biomarker in predicting post-treatment outcomes in patients with early hepatocellular carcinoma

BACKGROUND

There have been great advances in hepatocellular carcinoma management over the last years. However, there are still no prognostic biomarkers that can identify patients who will benefit the most from curative treatments. We aimed to investigate whether sPD-L1 levels measured before curative treatment is a prognostic biomarker of survival in patients with HCC.

METHODS

HCC patients from a prospectively collected database were selected and soluble programmed death-ligand1(sPD-L1) levels were determined. The association of sPD-L1 levels and overall survival (OS) and disease-free survival (DFS) was assessed.

RESULTS

One hundred twenty-one patients with HCC were included. The best cut-off value of sPD-L1 for both DFS and OS was 96 pg/mL. Patients with a high sPD-L1 value (>96 pg/mL) had a shorter disease free survival and OS (hazard ratio 5.42, 95% confidence interval 2.28-12.91, p < 0.001, and hazard ratio 9.67, 95% confidence interval 4.33-21.59, p < 0.001). High sPD-L1 levels were associated with mortality independently from other known survival predictors. We found a positive correlation between sPD-L1 and PD-L1 expression in cancer cells (p = 0.01). In 16 out of 38 patients, sPD-L1 levels decreased from baseline value on week 6 after treatment and in 22 out of 38 patients, sPD-L1 levels increased from the baseline value. However, fluctuations of sPD-L1 in time had no influence on survival (p = 0.148).

CONCLUSION

We conclude that a high sPD-L1 level is a biomarkerfor a poor outcome in HCC. The predictive value of sPD-L1 levels for a successful anti-PD1/PD-L1 therapy should be investigated in the future.

Nivolumab for Advanced Hepatocellular Carcinoma with Multiple Lung Metastases after Sorafenib Failure

Over the past decade, standard first-line systemic treatment of advanced hepatocellular carcinoma (HCC) has been based on sorafenib, a multi-kinase inhibitor. Regorafenib, another tyrosine kinase inhibitor, is the only second-line therapy that has been globally approved after progression under sorafenib treatment. Recently, immunotherapeutic agents have emerged as promising treatment options in many different malignancies, including advanced HCC. Nivolumab is the first immunotherapy approved by the Food and Drug Administration for use in HCC patients with advanced-stage second-line after sorafenib failure. In this report, a case of advanced HCC with multiple lung metastases in which a complete response and maintained progression-free status was achieved with nivolumab, following the failure of transarterial chemoembolization and sorafenib is presented. We hope this report may help expand the clinical application of second-line treatment.

Current Status and Future Direction of Immunotherapy in Hepatocellular Carcinoma: What Do the Data Suggest?

Most patients with hepatocellular carcinoma (HCC) are diagnosed at an advanced stage of disease. Until recently, systemic treatment options that showed survival benefits in HCC have been limited to tyrosine kinase inhibitors, antibodies targeting oncogenic signaling pathways or VEGF receptors. The HCC tumor microenvironment is characterized by a dysfunction of the immune system through multiple mechanisms, including accumulation of various immunosuppressive factors, recruitment of regulatory T cells and myeloid-derived suppressor cells, and induction of T cell exhaustion accompanied with the interaction between immune checkpoint ligands and receptors. Immune checkpoint inhibitors (ICIs) have been interfered this interaction and have altered therapeutic landscape of multiple cancer types including HCC. In this review, we discuss the use of anti-PD-1, anti-PD-L1, and anti-CTLA-4 antibodies in the treatment of advanced HCC. However, ICIs as a single agent do not benefit a significant portion of patients. Therefore, various clinical trials are exploring possible synergistic effects of combinations of different ICIs (anti-PD-1/PD-L1 and anti-CTLA-4 antibodies) or ICIs and target agents. Combinations of ICIs with locoregional therapies may also improve therapeutic responses.